Psilocybin has been shown to induce fast and sustained symptoms improvements across various psychiatric conditions, yet its long-term mechanisms of action are not fully understood. Initial evidence suggests that longitudinal functional and structural brain changes implicate fronto-striatal-thalamic (FST) circuitry, a broad system involved in goal-directed be...
Memory encoding depends on the joint convergence of substrate readiness, internal drive, environmental input, and a permissive temporal-physiological state. The same logic recurs across vertebrate learning systems: hippocampal-dependent spatial and schema-modulated memory (the Navigia substrate in the Systema Behavorum taxonomy), filial imprinting in the chi...
Psilocin, a naturally occurring hallucinogenic component of magic mushrooms, exerts notable psychoactive effects in both humans and rodents. However, the underlying mechanisms remain not fully understood. Blood-oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) is a valuable tool in many preclinical and clinical trials for invest...
OBJECTIVE: Psychedelics such as psilocybin are known for their hallucinogenic properties and have also been reported to produce long-lasting therapeutic effects in depression and possibly also other psychiatric disorders. Several lines of evidence suggest that psilocybin exerts its effects through activation of 5-HT2A receptors located postsynaptically to se...
The study hypothesis is that the antidepressant effect of psilocybin is mediated by a normalization of the functioning of the positive valence system. Depressive states, especially moderate to severe depressions that associate a certain level of anhedonia, produce an overvaluation of the cost of efforts and an infra-evaluation of the possible rewards derived...
Recent advancements in the study of psilocybin and its active metabolite psilocin have highlighted their unique psychedelic properties and potential therapeutic applications, particularly in the rapid and sustained treatment of depression. However, the potent acute psychedelic effects of psilocybin necessitate a deeper understanding of the neural mechanisms ...
Recent advancements in the study of psilocybin and its active metabolite psilocin have highlighted their unique psychedelic properties and potential therapeutic applications, particularly in the rapid and sustained treatment of depression. However, the potent acute psychedelic effects of psilocybin necessitate a deeper understanding of the neural mechanisms ...
ABSTRACT BACKGROUND AND PURPOSE: There is surging interest in the therapeutic potential of psychedelic compounds like psilocybin in the treatment of psychiatric illnesses like major depressive disorder (MDD). Recent studies point to the rapid antidepressant effect of psilocybin; however, the biological mechanisms underlying these differences remain unknown. ...
Molecular brain imaging by positron emission tomography (PET) and single photon emission computer-tomography (SPECT) entails the mapping of the cerebral distribution of radiopharmaceuticals that track physiological processes such as blood perfusion and glucose metabolism, or the abundance in brain of specific molecular targets such as neuroreceptors. PET and...
The full therapeutic potential of serotonergic psychedelics (SP) in treating neuropsychiatric disorders, such as depression and schizophrenia, is limited by possible adverse effects, including perceptual disturbances and psychosis, which require administration in controlled clinical environments. This study investigates the synergistic benefits of combining ...
The distinct subjective effects that define psychedelics such as LSD, psilocybin or DOI as drug class are causally linked to activation of the serotonin 2A receptor (5-HT2A R). However, some aspects of 5-HT2A R pharmacology remain elusive, such as what molecular drivers differentiate psychedelic from non-psychedelic 5-HT2A R agonists. We developed an ex vivo...
Background SAPAP3-knockout (KO) mice develop excessive self-grooming behavior at 4-6 months of age, serving as a model for obsessive-compulsive disorder (OCD). Given that anxiety often precedes OCD diagnosis in humans, this study investigated whether juvenile SAPAP3-KO mice exhibit anxiety-like behaviors before developing the self-grooming phenotype, and whe...
Psilocybin, a naturally occurring, tryptamine alkaloid prodrug, is currently being investigated for the treatment of a range of psychiatric disorders. Preclinical reports suggest that the biological effects of psilocybin-containing mushroom extract or "full spectrum" (psychedelic) mushroom extract (PME), may differ from those of chemically synthesized psiloc...
Psychedelics belong to the oldest psychoactive drugs. They arouse recent interest due to their therapeutic applications in the treatment of major depressive disorder, substance use disorder, end-of-life anxiety,= and anxiety symptoms, and obsessive-compulsive disorder. In this review, the current state of preclinical research on the mechanism of action, neur...
Abstract Psilocybin, a naturally occurring, tryptamine alkaloid prodrug, is currently being investigated for the treatment of a range of psychiatric disorders. Preclinical reports suggest that the biological effects of psilocybin-containing mushroom extract or “full spectrum” (psychedelic) mushroom extract (PME), may differ from those of chemically synthesiz...
Psilocybin, a naturally occurring hallucinogenic component of magic mushrooms, has significant psychoactive effects in both humans and rodents. But the underlying mechanisms are not fully understood. Blood-oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) is a useful tool in many preclinical and clinical trials to investigate ps...
The effects of context on the subjective experience of serotonergic psychedelics have not been fully examined in human neuroimaging studies, partly due to limitations of the imaging environment. Here, we administered saline or psilocybin to mice in their home cage or an enriched environment, immunofluorescently-labeled brain-wide c-Fos, and imaged cleared ti...
Hallucinogenic agents have been proposed as potent antidepressants; this includes the serotonin (5-HT) receptor 2A agonist psilocybin. In human subjects, psilocybin alters functional connectivity (FC) within the default-mode network (DMN), a constellation of inter-connected regions that is involved in self-reference and displays altered FC in depressive diso...
Recent studies suggest that the antidepressant effects of the psychedelic 5-HT2A receptor agonist psilocybin are mediated through its modulatory properties on prefrontal and limbic brain regions including the amygdala. To further investigate the effects of psilocybin on emotion processing networks, we studied for the first-time psilocybin's acute effects on ...
